Split common usbserial function. PL2303 skeleton

include/grub/usbserial.h

@@ -0,0 +1,31 @@
+/* serial.h - serial device interface */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2010  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef GRUB_USBSERIAL_HEADER
+#define GRUB_USBSERIAL_HEADER	1
+
+void grub_usbserial_fini (struct grub_serial_port *port);
+
+void grub_usbserial_detach (grub_usb_device_t usbdev, int configno,
+			    int interfno);
+
+int
+grub_usbserial_attach (grub_usb_device_t usbdev, int configno, int interfno,
+		       struct grub_serial_driver *driver);
+#endif